Leak-detecting apparatus for oil well casings



April 1950 J. R. LOCKETT 2,502,853

LEAK-DETECTING APPARATUS FOR on. WELL CASINGS Filed April 16, 1948 Patented Apr. 4, 1950 LEAK-DETECTING APPARATUS FOR OIL WELL CASINGS John B. Lockett, Columbus, Ohio Application April 16, 1948, Serial No. 21,426

Claims. (Cl. 73-155) This invention dealswith leak-detecting apparatus of the type used in determining the presence of a liquid-admitting leak or break occurring within the walls of an oil well casing- The primary objective of the invention is the provi-- sion of mechanically eflicient, yet economical apparatus for determining the presence of liquidadmitting leaks or breaks within an oil Well casing and the locations of such leaks with respect to the ground surface, in order that the casing may be repaired without undue delay and extensive inspection of the entire casing.

It is another object of the present invention to provide apparatus for detecting liquid-admitting breaks or openings within an oil well casing which comprises a device for attachment to a lowering and raising cable and for insertion within an oil well casing to indicate by audible signal means the absence or presence of liquid-admitting openings occurring within the casing.

It is a further object of this invention to provide apparatus of the character described which comprises an air whistle having 'an associated compressed air storage tank for supplying air to the whistle to produce a continuous audible sound during downward travel of the device through the well casing, and which is constructed so as to collect liquids admitted through a break in the casing upon passage of the apparatus immediately below such break whereby to dampen or cause the discontinuance of audible sound from the whistle, thereby notifying operators at the ground surface of the presence of such a break, and making it possible to determine the depth of such a break by measurement of the lowering cable at the time the signal ceases.

For a more detailed explanation of the present invention,reference is made to the following detailed description and the accompanying drawing, wherein:

Fig. 1 is a medial vertical sectional view taken through a leak-detectin mechanism embodying the aspects of the present invention, and disclosing its operational relationship toan oil well casing;

Fig. 2 is a horizontal sectional view taken along the line 22 of Fig. 1.

With reference to the drawing, it will be seen that the present invention makes use of a body generally designated by the numeral 5 which comprises a pair of annular metallic plate-like members 6 and I between which are interposed a plurality of outwardly extending annular gasket members 8, and which are rigidly joined by a plurality of spaced fastening devices 9. The

gasket members 8 of the body may be formed from any suitable yieldable material, such as leather, rubber, or one 01' the yieldable synthetic resins, and are adapted for close-fitting wiping engagement with the inner wall of a tubular well casing ID of the type used to form a casing wall for an oil well bore for purposes of retaining an earth wall II, and preventing the latter from entering within the well shaft.

Advantageously, a pair of the fastening devices 9 may be formed so as to constitute a U-shaped bail member l2 by which the body may be easily connected with the end of a lowering and raising cable l3 for passage through the well casing.

The lower plate-like member I of the body is formed centrally with an upwardly opening cup or cavity H which terminates at its lowermost end in a screw threaded socket l5. Disposed substantially in the bottom of the cup I! is a whistle-producing device I 6 which is formed integral with the bottom wall of the cavity l4, and which is provided with a pair of oppositel registering openings communicating with a central air passage I! which extends through the lower portion of the cup member and communicates with the screw-threaded socket l5. Intersecting the air passage I 1 is a transversely disposed valve chamber l8 which contains a screw-threaded needle valve I! which is adjustable to vary the opening of the passage l1 and to control the passage of air therethrough.

Maintained in threaded engagement with the socket ii of the body is the screw-threaded neck portion 20 of a compressed gas supply tank or receptacle 2|. The neck portion 20 of the tank is formed with an axially disposed opening 22 through which compressed gas may be discharged from the tank into the lower end of the air passage 11. The tank is further provided with a spring-loaded charging valve 23 or the type normally used in conjunction with pneumatic tires or other pneumatic apparatus, for the purpose of introducing compressed gas within'a receptacle by means of the ordinary flexible compressed air supply hose and nozzle.

In operation, the compressed gas tank 2| is threaded within the socket I5 of the body, and with the needle valve I9 in a closed position, compressed gas is introduced within the tank by way of the charging valve 23. Prior to lowering the apparatus within the casing I0, the needle valve I9 is adjusted so as to admit a constant stream of gas through the air passage l1 and to the whistle device IS, in order that a continuous audible whistle is produced. At this time, the

apparatus is lowered within the casing II, andallowed to descend at a relatively slow rate toward the bottom of the well. Durin passage of the apparatus through the casing, the presence of a liquid-admitting opening or break, such as is indicated by the numeral II of the drawin will be detected upon passage of the body immediately below the plane of such opening, as water or other liquids introduced within the casing through the break 24 will be deposited upon the upper surface of the body, and will immediately be collected within the cup ll thereof, thereby closing off the whistle opening and dampening or entirely extinguishing the audible sound emitted thereby. Upon cessation of the whistle, an operator positioned at ground level is apprised of the presence of liquid within the cup, and immediately stops descent of the body. At this time, a measurement of the lowering cable may be taken to determine the depth or relative position of the break or opening 24 in relation to the ground surface.

Due to the close-fitting and wiping engagement of the gasket members i of the body, it is necessary to provide for the release of air below the signal apparatus, as the same travels downwardly through the casing ll. Toward this end, the lower member I of the body is provided with an upwardly extending vent opening 25 through which air is free to pass from one to the other side of the body during lowering or raising operations.

In view of the foregoing, it will be seen that the present invention provides a mechanically eflicient device for detecting the presence of breaks or leaks occurring within an oil well casing, and additionally to determine the rela-.

tive location of such breaks with reference to the ground surface. Leak detection devices of the type formed in accordance with the present invention are characterized by their structural simplicity, their ease of operation, and their economy of manufacture, operation and maintenance.

While a present preferred embodiment of this invention has been disclosed in detail, it will be manifest that various modifications as to constructional details and design may be accomplished without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. Apparatus for determining liquid-admittina openings within a well casing comprising a body for lowering within a well casin and for closefitting wiping engagement with the walls thereof, said body being provided upon its upper surfaces with a cavity for the reception of liquids admitted through an opening in the walls of said casing upon passage of said body below the plane of such opening, and whistle means carried by said body and having a whistle opening communicating with the cavity of said body for emitting audible sound in the absence of liquid within the cavity of said body.

. 2. Apparatus for determining the depth of liquid-admitting openings occurring within a well casing comprising a body provided with outwardly extending sides for wiping engagement with the walls of a well casing and a centrally disposedliquid-receiving cavity, the cavity of said body serving to collect liquids admitted through an opening occurring within a well cas- 4 ing when said body is lowered therein below the plane of such an opening, and audio-signal means carried by said body and communicating with the cavity thereof for emitting a constant audible signal in the absence of liquid within the cavity of said body.

3. Apparatus for determining the depth of liquid-admitting openings occurring within the walls of the well casing comprising a body for lowering within a well casing, said body being provided with outwardly projecting side members for wiping engagement with the walls of a well casing and a centrally disposed cavity for the reception of liquids admitted through an opening occurring within the walls of such casin upon passage of said body below the/plane of such an opening, a whistle opening disposed in the bottom portion of the cavity of said body. and a compressed gas supply tank carried by said body and communicating with said whistle opening for producing a constant audible sound in the absence of liquid within the cavity of said y.

4. Apparatus for determining the depth of liquid-admitting openings occurring within the walls of a well casing comprising a circular platelike body for lowering within an oil well casin and for close-fitting wiping engagement with the walls thereof, said body being provided with an upwardly opening cavity for the reception of liquids admitted through an opening occurring within an oil well casing upon passage of said body below the plane of such opening. a whistle device disposed substantially within the bottom of the cavity of said body, and a compressed gas supply tank carried by said body and communicating with said whistle device for supplying whistle-producing gas thereto. said whistle device being continuously operable in the absence of liquid within the cavity of said body and inoperable in the presence of liquid therein.

5. Apparatus for determining the depth of liquid-admitting openings occurring within the walls of a well casing comprising a circular plate- 5 like body for lowering within an oil well casing and for close-fitting wiping engagement with the walls thereof, said body being provided with an upwardly opening cavity for the reception of liquids admitted through an opening occurring within an oil well casing upon passage of said body below the plane of such opening, a whistle device disposed substantially within the bottom of the cavity of said body, a compressed gas supply tank carried by said body and communicating with said whistle device for supplying whistle-producing gas thereto, said whistle device being continuously operable in the absence of liquid within the cavity of said body and inoperable in the presence of liquid therein, and valve means associated with said whistle device for controlling the passage of gas from said tank to said whistle.

JOHN R. LOCKETI.

REFERENCES CITED UNITED STATES PATENTS Name Date Di Renzo May 18, 1948 Number 

